It might be just flamebait to even mention it, but those of us who are writing software which conforms to the Open Source Definition or the Four Freedoms (most often both) sooner or later need to decide whether to call it open source software, free software, or libre software, with the most controversy tending to surround whether people are trying to water down the meaning of open source (for example see What is open source?).
The only reason I bother to write about this is that Martin Fowler, in his Semantic Diffusion article, points out that this is completely par for the course when a concept is getting popular. He has some great examples of this (I am old enough to remember how for a time everything was described as "object-oriented").
So if open source is like the other terms Fowler discusses, there isn't a need to start a big panic. As long as we have a critical mass of people using the word open source to refer to software meeting the open source definition, the odds are good that the meaning won't drift too far and too permanently.